HOW FAST FUSES BURN

Question: How fast will different types of fuses burn?

Warren Fusco

Sci 8-1

BACKGROUND RESEARCH

Gunpowder is the main ingredient in fuses. In fuses, gunpowder is

wrapped tightly with a small string to keep it together. Gunpowder has

been used in fuses since ancient Chinese times, and it has been used as

an initial charge for explosives and fireworks through the present day1.

Visco is the most common fuse in the world. Visco is popular

because it is cheap and holds together well2. Visco fuses will be tested in

this study. Another common fuse that is tested in this study is called the

Flying Fish fuse. Flying Fish fuses burn fast and burn well. Two other

home made fuses will be tested in this study. One home made fuse is

made with plain string, and the other is made with string, wax, and

ground up match heads.

HYPOTHESIS

I expect that the Flying Fish fuse will burn the fastest because it was made by professionals and holds together well. Flying Fish fuses are also very thin and I expect that this would make it burn at a fast rate. If the fuse is thin and tightly wrapped then the fuse will burn faster because it is more compressed and it takes a shorter time for the gunpowder to ignite the other gunpowder in the fuse. The tight wrap will ensure that the fuse stays together and will spread the flame throughout the fuse.

MATERIALS

FUSES and FUSE CONSTRUCTION

• Four 1 foot lengths of regular Visco fuse

• Four 1 foot lengths of Flying Fish fuse

• Four 1 foot lengths of home made string fuse

• Home made combustible fuse:• Four 1 foot lengths of

string

• 100 match heads

• Candle wax as needed

EXPERIMENT MATERIALS

• 1 butane fire stick

• Two stopwatches

• 1 camera

• 1 piece of wood

• Screws to hold fuses in place

PROCEDURE: FUSE CONSTRUCTION

FUSE CONSTRUCTION1. Cut Flying Fish fuse and Visco fuse into four 1 foot

lengths.2. Cut regular string fuse into four 1 foot lengths.3. Home Made Combustible Fuse:

A. Cut string into a 4 foot length.B. Grind 100 match heads into powder and put into 4

foot line on a piece of waxed paper.C. Melt enough wax from a candle to cover the entire

length of the string.D. Dip entire length of string into melted wax.E. Lay the string on top of the ground match heads and

roll to ensure that string is covered with the powder.F. Let wax cool and solidify.G. Cut home made fuse into four 1 foot lengths.

PROCEDURE: FUSE CONSTRUCTION

Flying Fish Visco Plain String Home Made

PROCEDURE: TEST PROCESS

Experimental Process

1. Collect all materials and instruments.

2. Attach one Flying Fish fuse to piece of wood using screws.

3. Zero stopwatches.

4. Light fuse while starting stop watches.

5. Stop one watch at six inch mark.

6. Stop second watch at complete burn.

7. Record times.

8. Repeat steps 2 through 7 for remaining three Flying Fish fuses.

9. Repeat steps 2 through 8 for remaining three types of fuses.

PROCEDURE: TEST PROCESS

Fuse in holder before test Fuse during test

String fuse

Visco fuseFlying Fish fuse

Home Made fuse Visco fuseFlying Fish fuse

Home Made fuse String fuse

DATA

• Visco fuse makes lots of sparks and burns at an average rate of 15.75 seconds per fuse

• Flying Fish fuse makes purple sparks and burns at an average rate of 20.75 seconds per fuse

• String fuse fails to stay lit and never completely burns without being re-lit.

• Home made fuse burns slowly but eventually burned completely. Average burn rate was 901 seconds per fuse.

Visco

Flying Fish

String

Home Made

Test 1 17 22 N/A 901

Test 2 15 20 N/A 976

Test 3 15 21 N/A 888

Test 4 16 20 N/A 839

Times in seconds

ANALYSIS

Custom Fuse String Visco Fuse Flying Fish Fuse0

100

200

300

400

500

600

700

800

900

1,000

6 inches

12 inches

Avera

ge T

ime T

o B

urn

(sec)

The bar chart below shows the average burn times for each fuse. The chart shows that the professionally made fuses burned muchquicker than the home made fuses.

Did

Not

Com

ple

tely

Burn

CONCLUSION

The fastest of all the fuses was the Visco fuse. The reason why this fuse was the fastest is because of how tightly packed the gunpowder was in it. My hypothesis that the Flying Fish fuse would burn fastest was wrong, but now I know how efficient each fuse is and their strengths and weaknesses. It is possible that the Visco fuse is faster than the Flying Fish fuse because the Visco fuse was stiffer than the Flying Fish fuse, which could indicate that the gunpowder was more tightly packed in the Visco fuse.

Even though the Flying Fish did not burn as fast, it may be a good choice because it makes different colors and burns at a slower, more controlled rate. Depending on home made fuses is not recommended because they are inconsistent and take a long time to make. These reasons and the low cost of professionally made fuses make them a better choice than home made fuses for home use.

APPLICATION AND FURTHER

EXPLORATIONSMy experiment can be helpful in real life situations because it could determine life or death. If the wrong type of fuse was put on a firework, and the fuse burned too quickly, injury to the user could happen. Knowing accurate fuse burn times can prevent such an event. Similar information would be needed for other uses, like demolition, for example.

The conclusion shows that the tightness of the packing of gunpowder may affect burn times. Future experimentation could measure this packing tightness, and see if it has a measurable impact on burn times.

CITATIONS

1. Langone, John. National Geographic's How Things Work: Everyday Technology Explained. Washington, D.C.: National Geographic, 1999. Print.

2. "Visco Fuse." Wikipedia. Wikimedia Foundation, 14 Nov. 2014. Web. 17 Nov. 2014.